1. Field of the Invention
This invention relates to method and apparatus for the optical entry of data through an interface device to data processing equipment, and more particularly to an optical keyboard, which is interfaced with a computer to permit physically handicapped users to enter data into the computer.
2. Description of the Prior Art
It is well known in the art to utilize special purpose data input devices in place of the standard keyboard used to input data to electric typewriters and computers. The data input is supplied through an interface device that obviates the need to input data mechanically, in a conventional manner through a typewriter or a keyboard terminal of a computer. A wide spectrum of input devices are available for use by the physically handicapped, as in the case of individuals unable to execute the necessary hand movements needed for operating a mechanical keyboard. Interface devices are also available for those unable to verbalize data because of physiological handicaps, injury or other causes.
U.S. Pat. No. 3,059,064 discloses a data converter, by which visible information, such as a printed text, is converted to audible speech or photographs, to audio signals. This device has specific application for communication with non-sighted individuals, as well as, the illiterate. In this early development, a printed text is read and converted to audible speech. The output audible signals are in the form of speech quite similar to the audible speech provided by an individual reading the printed text outloud. In this manner, data imput, in the form of printed text, is converted to audio electrical signals representing speech.
More recently, as disclosed in the U.S. Pat. No. 3,761,877, light-emitting styluses, known as light pens, have been developed as an alternative to the conventional keyboard for supplying graphical data input to computers, displays, and other peripheral equipment. A graphic data tablet serves as a graphical interface between the input supplied by use of the light pen to a microprocessor. The light pen is moved by an operator over the flat writing surface of the graphic data tablet. The position of the light pen is detected by various means and associated circuitry converts the light pen position into digital or analog signals. The signals are a function of the position of the light pen on the tablet. The use of the light pen requires manual dexterity, and is not available to an operator who is physically or sight impaired.
U.S. Pat. Nos. 4,190,883 and 4,303,916 disclose apparatus for interfacing data processing equipment with an input terminal operable to receive input through a light pen. The disclosed light pen carries a light sensor, which develops a coded signal indicative of a specific selected item, when the item is illustrated with the light pen. When the light pen is placed upon a selected character of the input terminal, an optoelectric converter is supplied with light pulses representative of the selected character. In time coincidence with the light pulses, a digital code corresponding to the character appears on the output terminal. The code is transmitted to the RAM of the microprocessor and is capable of being reproduced as output in the form of alphanumeric text.
A wide variety of products are also available to provide nonverbal communication by the handicapped. These products enable an individual, not having the ability to verbally communicate, to transmit messages through various interface devices for converting input signals to output in either a printed or audio format.
U.S. Pat. No. 4,414,537 discloses a digital data entry glove interface device for use by the hearing impaired. A glove is equipped with sensors and associated electronic logic for use by one skilled in the use of a sign language. This permits a deaf or hearing impaired user wearing the data entry glove to input data to a receiving device by forming his or her hand into the character positions defined by the Signal Hand Manual Alphabet. Thus, a user who is hearing impaired and having no typing or other keyboard skills, can input information to a computer and communicate visually with others.
U.S. Pat. No. 3,818,448 discloses communication apparatus for non-verbal, handicapped persons who are unable to make use of sign language or other conventional communicating skills. A cabinet is provided with an array of indicator lamps and has acoustical devices, together with circuit means connectable with switches, which are operated by movement of some portion of the person's body to energize selected lamps, combinations thereof, or the acoustical devices. The switch means for controlling energization of the lamps can be actuated by left and right movement of the person's head. One switch may be used to select a particular row of indicators, while anothe switch is used to select a column.
U.S. Pat. No. 3,986,030 discloses an eye-motion operable keyboard, which includes a light source for directing a light ray at an eye of an operator. The light reflected from the eye of the operator actuates a selected light responsive sensor, arranged in a keyboard pattern on a panel. Each sensor has an output, which is connected to electrically actuated keys. The keys are positioned on a keyboard and are selectively actuated by the operator-reflected light striking one of the light responsive sensors. Preferably the light source is an infrared light source, and the sensors are responsive to rays of infrared light.
Not only are there known a wide variety of devices to permit handicapped individuals to utilize data processing equipment and other types of equipment of remote control by interaction with the human eye or light source, interface devices are also known for the sight operation of telephones. U.S. Pat. No. 4,081,623 discloses an optical interface for operating a telephone. This device also utilizes the "red-eye" effect of utilizing light reflected from the cornea of the eye to energize a sensor for transmitting electric signals to a logic circuit. Thus commands are transmitted to the logic circuit according to the number of times in sequence the eye is winked, or according to the length of time the eye is closed. A display unit displays digital information to the operator as it is sequenced through the digits available to the operator. The operator can stop the sequence at the appropriate digit by winking his eye. By selecting the proper sequence of digits, a telephone call can be placed.
Further examples of devices for the optical entry of data to data processing equipment, are disclosed in U.S. Pat. Nos. 4,205,304 and 3,478,220. Each of these devices utilize an optical device for actuating photosensitive devices positioned in a selected array. A series of light sources along a vertical axis of the array transmits a beam of light to corresponding photosensors on the opposite vertical side of a frame. The same arrangement is utilized to activate photosensors positioned along the horizontal axis of the array. The light sources actuate the photosensitive elements to emit output signals, which corresponds to an X-Y position in a coordinate system formed by the array of photosensitive devices. The output is then transmitted to a computer for carrying out a specific function corresponding to the input received.
U.S. Pat. No. 4,205,304 discloses a selection system circuit in which a signal corresponding to a selected position in a X-Y coordinate system is generated in response to the interruption of light transmission between a selected light emitter and light detector. A corresponding output signal is generated and is decoded for a selected control purpose; for example, enablement of a control mechanism.
While it is well known to transmit data and information to data processing equipment by other than manual keyboarding operations, for the benefit of both the physically handicapped and the nonverbal handicapped, the known devices are not readily adaptable to data processing equipment that is conventionally operated through a keyboard terminal. The known devices require substantial modification to the input terminal of the data processor to receive information in form not transmitted by a conventional keyboard. Because of the extensive modifications that are required to accommodate the known systems, each system must be customized to accommodate the optical entry of data. Overall, data entry equipment is not readily available for the physically handicapped. The equipment that is available is expensive, and not economically accessible to the handicapped to the extent to permit them to use the equipment to lead productive lives and pursue gainful employment. Therefore, there is need for interface apparatus to permit the optical entry of data through conventional data processing equipment.